Bridging the Gap: Science and Technology Policy in the (Bio)Engineering Classroom.

Engineers and scientists have a key role to play in the creation and implementation of government policy. Policymakers need access to the technical expertise that is critical to our national progress and security; however, this need is often overlooked by engineering students, faculty, and professionals. Even though a substantial fraction of scientists and engineers end up pursuing jobs in government, engineering curricula do not usually provide any background in policy and for many, the policy-making process remains a black box.

A Library of Fluorinated Electrophiles for Chemical Tagging and Materials Synthesis.

Various applications could benefit from new fluorinated molecules that offer chemical handles for quickly functionalizing reactive surfaces and molecules. Herein, we report the synthesis of a library of fluorinated molecules that contain nonafluoro-tert-butyl groups and electrophilic handles, mostly acrylates and acrylamides. Featuring a variety of hydrophobic and hydrophilic linkers, these molecules could find use in polymer chemistry, biomaterials, biomedical imaging, and protein tagging.

Adsorption and release of siRNA from porous silica.

Porous silica particles are potential transfection agents for nucleic acid-based therapies because of their large specific surface areas and pore volumes and the ease with which they can be chemically modified to maximize the loading of cargo and to effect targeting in vivo. Here, we present a systematic study of the effects of pore size and pore modification on the adsorption and release of short, interfering RNA (siRNA) from a mesoporous silica particle developed in our laboratory. Using adsorption isotherms and release experiments, we found that the short polyamine diethylenetriamine was the best chemical modification for achieving both the adsorption and release of large amounts of siRNA.

Microspheres targeted with a mesothelin antibody and loaded with doxorubicin reduce tumor volume of human mesotheliomas in xenografts.

Background: Malignant mesotheliomas (MMs) are chemoresistant tumors related to exposure to asbestos fibers. The long latency period of MM (30-40 yrs) and heterogeneity of tumor presentation make MM difficult to diagnose and treat at early stages. Currently approved second-line treatments following surgical resection of MMs include a combination of cisplatin or carboplatin (delivered systemically) and pemetrexed, a folate inhibitor, with or without subsequent radiation.

A multifunctional mesothelin antibody-tagged microparticle targets human mesotheliomas.

Pleural and peritoneal mesotheliomas (MMs) are chemoresistant tumors with no effective therapeutic strategies. The authors first injected multifunctional, acid-prepared mesoporous spheres (APMS), microparticles functionalized with tetraethylene glycol oligomers, intraperitoneally into rodents. Biodistribution of APMS was observed in major organs, peritoneal lavage fluid (PLF), and urine of normal mice and rats.

Differences in gene expression and cytokine production by crystalline vs. amorphous silica in human lung epithelial cells.

Background: Exposure to respirable crystalline silica particles, as opposed to amorphous silica, is associated with lung inflammation, pulmonary fibrosis (silicosis), and potentially with lung cancer. We used Affymetrix/GeneSifter microarray analysis to determine whether gene expression profiles differed in a human bronchial epithelial cell line (BEAS 2B) exposed to cristobalite vs. amorphous silica particles at non-toxic and equal surface areas (75 and 150 × 106μm2/cm2).

Thiourea/proline derivative-catalyzed synthesis of tetrahydrofuran derivatives: a mechanistic view.

A thiourea/proline derivative-catalyzed synthesis of linear α-substituted tetrahydrofuran/pyran derivatives starting with lactol substrates is presented. This study demonstrates the utility and potential complications of using (thio)urea/proline cocatalysis as each of these catalysts is necessary to provide the observed reactivity, but a time-dependent decrease in enantioselectivity is observed. New mechanistic insights into (thio)urea/proline cocatalysis are presented.

Increased efficacy of doxorubicin delivered in multifunctional microparticles for mesothelioma therapy.

New and effective treatment strategies are desperately needed for malignant mesothelioma (MM), an aggressive cancer with a poor prognosis. We have shown previously that acid-prepared mesoporous microspheres (APMS) are nontoxic after intrapleural or intraperitoneal (IP) administration to rodents. The purpose here was to evaluate the utility of APMS in delivering chemotherapeutic drugs to human MM cells in vitro and in two mouse xenograft models of MM.

Enhanced uptake of porous silica microparticles by bifunctional surface modification with a targeting antibody and a biocompatible polymer.

Strategies were developed by which mesoporous microparticles were modified on their external surfaces with tetraethylene glycol (TEG), a protein, or both, leaving the pore surfaces available for modification with a separate moiety, such as a dye. Only particles bifunctionally modified with both TEG and a cell-specific antibody were taken up specifically by a targeted cancer cell line. In contrast to similarly functionalized nanoparticles, endocytosed microparticles were not contained within a lysosome.

Use of bifunctional ureas to increase the rate of proline-catalyzed alpha-aminoxylations.

The rate of the proline-catalyzed alpha-aminoxylation of aldehydes is significantly increased in the presence of a bifunctional urea. Structure-activity relationship data indicate that both an amine and a urea are crucial for rate enhancement. The evidence presented herein suggests that this rate enhancement originates from the hydrogen bonding interaction between the bifunctional urea and an oxazolidinone intermediate to increase the rate of enamine formation.

Microencapsulated linear polymers: "soluble" heterogeneous catalysts.

A new strategy for supporting catalysts based on the microencapsulation of linear polymers is presented. In this paper, we present a DMAP capsule that is capable of catalyzing acylation reactions. The catalyst is compared to DMAP on cross-linked and linear polystyrene, as well as small molecule DMAP.

Rapid self-assembly of core-shell organosilicon microcapsules within a microfluidic device.

The preparation of hierarchically structured organosilicon microcapsules from commercially available starting materials is described. Using a microfluidic device, an emulsion of dichlorodiphenylsilane is formed in a continuous phase of aqueous glycerol. The silane droplets undergo hydrolysis, condensation, and crystallization within minutes to form self-assembled, core-shell microcapsules.